Spinning machine

ABSTRACT

In a spinning machine for shaping a blank into a product of a desired configuration without using a metal mold, there are provided a rotary shaft, a push rod, the rotary shaft and push rod cooperating to clamp therebetween a flat plate shaped blank for rotating the same, a back-up roller having a peripheral contour conforming to a portion of the inside contour of a spinned product, means to urge the back-up roller against one side of the blank, means to move the back-up roller along a predetermined path conforming to the inside contour of the product, a work roll having a working edge of smaller radius of curvature than said back-up roller, means to urge the work roll against the opposite side of the blank with a predtermined definite axial spacing between the work roll and the back-up roller and means for moving the work roll to follow the movement of the back-up roller while maintaining the definite axial spacing with respect to the back-up roller.

Ashizawa 1 Jan. 8, 1974 1 i SPINNING MACHINE [75] Inventor:YoshimiAshizawa,Kanagawa,

Japan [73] Assignee: Toshiba KikaiKabushiltiKaisha;

Tokyo, Japan [22] Filed: July 31, 1972 [21] Appl. No.: 276,797

[30] Foreign Application Priority Data Aug. 11. 1971 Japan 46/6076 8 52us. C1. 72/81 [51] Int. Cl B211d 22/18 [58] Field of Search 72/80, 81,84, 85,

[56] References Cited UNITED STATES PATENTS $543,622 12/1970 Willard72/81 3,168,919 2/1965 Shutt 72/84 3,372,567 3/1968 Jensen et al. .172/80 3,427,846 2/1969 Viltschek et al... 72/81 426235 4/1890 Browning72/81 2.069198 2/1937 Cushwa 72/81 3,580,025 5/1971 Hayashi M 72/84Primary ExaminerRichard J. Herbst Att0rneyE. F. Wenderoth et a1.

[57] ABSTRACT In a spinning machine for shaping a blank into a productof a desired configuration without using a metal mold, there areprovided a rotary shaft, a push rod, the rotary shaft and push rodcooperating to clamp therebetween a flat plate shaped blank for rotatingthe same, a back-up roller having a peripheral contour conforming to aportion of the inside contour of a spinned product, means to urge theback-up roller against one side of the blank, means to move the back-uproller along a predetermined path conforming to the inside contour ofthe product, a work roll having a working edge of smaller radius ofcurvature than said back-up roller, means to urge the work roll againstthe opposite side of the blank with a predtermined definite axialspacing between the work roll and the back-up roller and means formoving the work roll to follow the movement of the back-up roller whilemaintaining the definite axial spacing with respect to the back-uproller.

3 Claims, 6 Drawing Figures Pmmmm 819R mmsss EMU 1 UP 3 FIG. I

PRIOR ART K FIG. 2 \r V SPINNING MACHINE BACKGROUND OF THE INVENTIONThis invention relates to a spinning machine, more particularly a shearspinning machine wherein a blank in the form of a metal plate is shapedinto a product of the desired configuration by a shear spinning processwhile the blank is clamped between a work roll and a back-up roll.

As diagrammatically shown in FIG. 1, according to the shear spinningprocess, a blank 1 in the form of a flat metal plate is clamped betweena rotary mother mold 2 which is mounted on a headstock of a lath, notshown, and a push rod 3 which is mounted on the tailstock of the lath,not shown, so as to rotate the blank and the push rod 3 as the rotarymold is rotated. While rotating the blank 1 in this manner, a work roll4 is moved from the center toward the periphery of the blank along theinclined surface of the mother mold, which in this case takes the formof a frustum of a'cone,

thereby forming a product as shown by dotted lines in FIG. 1. At anintermediate point of the spinning operation, the work roll assumes aposition indicated by 4a and the blank assumes a configuration as shownby 1a.

According to the shear spinning process, the work roll 4 is controlledsuch that the thickness ta of the product in the axial direction of theproduct or the lath will be equal to the thickness t, of the blank 1.With this process, the material of the blank 1 is moved in parallel inthe direction of the thickness of the blank by the shearing force sothat the outer diameter of the product is equal to the diameter Doof'the blank. Furthermore, during the oblique movement of the work roll4, stress is applied only in the direction of the thickness of the blankand no stress creates in the circumferential and radial directions.

However, since this method of spinning requires a mother mold having thesame diameter as the product, the cost of the metal mold increases withthe diameter of the product. Where it is necessary to harden the surfaceof the metal mold, the cost thereof is increased further. Provision of anumber of molds of different type and size require a large space andexpense.

SUMMARY OF THE INVENTION tion at any point which is equal to thethickness of the blank.

According to this invention there is provided a spinning machinecomprising a rotary shaft, a push rod, the rotary shaft and push rodcooperating to clamp therebetween a flat plate shaped blank for rotatingthe same, a back-up roller having a peripheral contour conforming to aportion of the inside contour of a spinned product, means to urge theback-up roller against one side of the blank, means to move the back-uproller along a predetermined path conforming to the inside contour ofthe product, a work roll having a working edge of smaller radius ofcurvature than said back-up roller,

means to urge the work roll against the opposite side of the blank witha predetermined definite spacing which is equal to the thickness of theblank as measured in the axial direction of the spinning machine betweenthe work roll and the back-up roller and means for moving the work rollto follow the movement of the back-up roller while maintaining thedefinite spacing with respect to the back-up roller.

BRIEF DESCRIPTION OF THE DRAWINGS In the accompanying drawing:

FIG. 1 is a diagram showing the principle of the construction andoperation of the prior art spinning machine;

FIG. 2 is a diagram showing the principle of the construction andoperation of a spinning machine adapted to manufacture a frusto conicalproduct;

FIG. 3 is a diagram similar to FIG. 2 where a bowl shaped product is tobe manufactured;

Flg. 4 is a plan view showing the detail of the construction of thespinning machine shown in FIG. 2;

FIG. 5 is a plan view showing the detail of the construction of thespinning machine shown in FIG. 3 and FIG. 6 is a side elevation of amechanism for moving the backup roller along a predetermined curvedpath.

DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG. 2 shows the principle ofthe construction and operation of the novel spinning machine adapted toshape a metal blank 1 into a frusto-conical product. The central portionof the blank I haying a thickness of t is clamped between a push rod 3mounted on a tailstock and a rotary shaft 6 mounted on a headstock of alath as will be described later with reference to FIGS. 4 to 6, wherebythe blank 1 is rotated together with a rotary shaft 6. On the inner sideof the blank 1 there is provided a freely rotatable back-up roller 5which is moved along the inner contour of the product by a mechanism tobe described later. The work roll 4 is moved to follow the movement ofthe back-up roller 5 while maintaining a definite axial spacingtherebetween. As clearly shown in the figures the work roll 4 has aworking edge of smaller radius of curvature than the back-up roller 5.The positions of the work roll 4 and the back-up roller 5 at anintermediate point of the working are shown by 4a and 5a, respectively.As before, the axial thickness of the product la is indicated by t,,.

In order to shape the blank 1 into the product lla by the shear spinningmethod the back-up roller 5 is positioned such that its generatingsurface assumes a straight line which is positioned at an angle 6 fromthe axis of rotation (angle 0 is equal to one half of the apex angle ofa cone), the back-up roller 5 is moved while keeping angle 0, and thework roll 4 is moved to follow the movement of the back-up roller 5while maintaining the constant axial spacing therebetween which is equalto the original thickness to of the blank.

FIG. 3 is a diagram illustrating a modified embodiment of the inventionin which a flat metal bank 1 is shaped into a product of a bowl orhemispherical shape. In this case, the surface generating of the backuproller is made to extend along an are having a radious R, and the backuproller 5 is moved along this are. On the other hand, the work roll 4 ismoved to follow the arcuate movement of the back-up roller such that theaxial spacing equal to the thickness to of the blank is alwaysmaintained between the work roll 4 and the follow-up roller 5 during thespinning operation. Thus, the blank 1 clamped between the rotary shaft 6and the push rod 3 is worked into a bowl with an inner surface having aradius of curvature of R.

As above described, the invention provides a novel spinning machinewhich can shape a blank into a product of a desired configurationwithout using any expensive metal mould by only one pass of-short timeand of very simple operation, thus saving the time and cost ofmanufacturing.

FIG. 4 shows a plan view of a spinning machine for carrying out thespinning operation outlined in connection with FIG. 2. As shown, thepush rod 3 is mounted on a tailstock 13 of a lath and the rotary shaft 6is mounted on a headstock l4 rotated by an electric motor 15. Work roll4 and back-up roller 5 are mounted on cross-slides l1 and 11a,respectively, through supports 7 and 7a and clamps 8 and 8a. The slides11 and 11a are operated by piston-cylinder assemblies 12 and 120,respectively, and are secured to saddles 9 and 9a which are slidablymounted on a common bed 10 which in turn is adjustable along guidegrooves 25.

In operation, bed 10 is set to the position shown in FIG. 4. This can bereadily accomplished by laterally moving the bed 10 along guide grooves25 and by rotating a base plate (not shown) which supports the entireassembly of bed 10, saddles 9, 9a and guide grooves 25 about a pivotshaft 30. The piston-cylinder assemblies 12 and 120 are operated tobring work roll 4 and backup roller 5 on the opposite sides of theblank 1. Then, cross-slides 11 and 11a are fixed to the saddles 9 and 9ato maintain work roll 4 and backup roller 5 at a given spacing equal tothe thickness of the blank. Thereafter, driving motor 15 is energized torotate the blank 1, and saddles 9 and 9a are concurrently moved on bed10 causing the work roll and back-up roller to travel toward theperiphery of the workpiece thereby spinning the blank 1 into afrusto-conical product. Since work-roll 4 and back-up roller 5 aremaintained at a definite axial spacing during the spinning operation theaxial thickness of the product at any point thereof is equal to theoriginal thickness of the blank. In other words, the blank is subjectedto a shear spinning operation so that any stress will not be created inthe product in the circumferential and radial directions.

In the modified embodiment shown in FIGS. 5 and 6, saddles 9 and 9awhich support cross slides 11 and 11a and piston cylinder-assemblies 12and 120 are slidably mounted on bed 10 in the same manner as in theprevious embodiment. The back-up roller 5 is mounted on a bracket 16which is guided to move along a curved guide groove 24 ofa guide blockby means of rollers 17 (only one of them is seen in FIG. 6) mounted onthe underside of bracket 16 to be received in groove 24. Guide block 20is supported by a pedestal 19 as shown in FIG. 6. The groove 24 and theperipheral surface of back-up roller 5 are shaped to have the sameradius of curvature R as the inner wall of the product. Thepiston-cylinder assembly 120 is connected to bracket 16 through pins 22and 23 and links 21 and 7a so that when saddle 9a is moved in thelongitudinal direction of bed 10, the bracket 16 and hence back-uproller 5 are moved along curved groove 24. As above described, to carryout the shear spinning operation it is necessary to maintain the workroll and the back-up roller always at a constant axial spacing which isequal to the original thickness of the blank. In other words, as theback-up roller 5 is moved always along a predetermined curved path, thatis guide groove 24, it is necessary to cause the work roll 4 to followthe movement of the back-up roller while maintaining the constant axialspacing. For the purpose of simplifying the drawing, although the workroll 4 is shown as directly mounted on the outer end of support 7, itshould be understood that, a mechanism including a guide groove and abracket identical to those described above is also provided for workroll 4 so as to cause it to move along a curved path. The curvatures ofthe work roll 4 and back-up roller 5 are the same as that of guidegroove 24.

To manufacture a bowl shaped product, bed 10, saddles 9 and 9a andcross-slides l1 and 11a are brought to the positions shown in FIG. 5,thereby bringing work roll 4 and back-up roller 5 to their initialpositions. Then, the saddles 9 and 9a are moved downwardly to move workroll 4 and the back-up roller 5 toward the periphery of the workpiece,along a predetermined curved path conforming to the contour of theproduct.

Although in the foregoing description, the work roll and backup rollerare moved along a predetermined curved path by using a guide blockhaving a curved guide groove it will be clear that such movement along apredetermined path can be provided by a well known profile control,digital control or program control. For example a program representingthe predetermined path is stored in an electronic computor to generatecommand signals for moving the work roll and back-up roll along thepredetermined path. Alternatively, instead of providing independentmechanisms including guide block 20, bracket 16, etc. for both work rolland back-up roller, these work roll and back-up roller may be moved inunison by means of a single mechanism.

Although the invention has been shown and described in terms of certainpreferred embodiments thereof it will be clear that many changes andmodifications may be made without departing from the true spirit andscope of the invention as defined in the appended claims.

What I claim is:

1. A spinning machine comprising a rotary shaft, a push rod, said rotaryshaft and said push rod cooperating to clamp therebetween a flap plateshaped blank for i rotating the same, a back-up roller having aperipheral contour conforming to a portion of the inside contour of aspinned product, means to urge said back-up roller against one side ofsaid blank, means to move said back-up roller along a predetermined pathconforming to the inside contour of said product, a work roll having aworking edge of smaller radius of curvature than said back-up roller,means to urge said work roll against the opposite side of said blank,means for maintaining a predetermined definite spacing between said workroll and said back-up roller while they are moved from the center ofsaid blank to the outer edge thereof, said spacing being equal to thethickness of said blank as measured in the axial direction of saidspinning machine, and means for moving said work roll to follow themovement of said back-up roller while maintaining said definite spacingsaid respect to said back-up roller, thereby shaping said blank into theproduct of the final tion substantially perpendicular to the directionof movement of said cross-slides.

3. The spinning machine according to claim 1 wherein said means formoving said back-up roller along a predetermined path includes astationary block having a curved groove of the shape conforming to theinside contour of the shaped product and means guided by said curvedgroove to move said back-up roller.

1. A spinning machine comprising a rotary shaft, a push rod, said rotaryshaft and said push rod cooperating to clamp therebetween a flap plateshaped blank for rotating the same, a back-up roller having a peripheralcontour conforming to a portion of the inside contour of a spinnedproduct, means to urge said back-up roller against one side of saidblank, means to move said back-up roller along a predetermined pathconforming to the inside contour of said product, a work roll having aworking edge of smaller radius of curvature than said back-up roller,means to urge said work roll against the opposite side of said blank,means for maintaining a predetermined definite spacing between said workroll and said back-up roller while they are moved from the center ofsaid blank to the outer edge thereof, said spacing being equal to thethickness of said blank as measured in the axial direction of saidspinning machine, and means for moving said work roll to follow themovement of said back-up roller while maintaining said definite spacingsaid respect to said back-up roller, thereby shaping said blank into theproduct of the final configuration by shear spinning performed by asingle pass.
 2. The spinning machine according to claim 1 wherein saidrotary shaft is mounted on a headstock of a lath, said push rod ismounted on a tailstock of said lath, said work roll and said back-uproller are mounted on cross-slides operated by piston-cylinderassemblies, said cross-slides are mounted on saddles which are mountedon a common bed to be movable in a direction substantially perpendicularto the direction of movement of said cross-slides.
 3. The spinningmachine according to claim 1 wherein said means for moving said back-uproller along a predetermined path includes a stationary block having acurved groove of the shape conforming to the inside contour of thEshaped product and means guided by said curved groove to move saidback-up roller.